96

No, this is not possible. There are a few reasons for that, but most important are that the only thing a mosquito injects is its own saliva, while the blood is sucked into the stomach where it is digested. To be able to infect other people HIV would need to be able to leave the gut intact and then also be able to replicate in the mosquitos which it cannot ...


56

Fever is a trait observed in warm and cold-blooded vertebrates that has been conserved for hundreds of millions of years (Evans, 2015). Elevated body temperature stimulates the body's immune response against infectious viruses and bacteria. It also makes the body less favorable as a host for replicating viruses and bacteria, which are temperature sensitive ...


28

It is possible for viruses to live in mutualistic relationships with their hosts, these associations are often overlooked due to the devastating effect that many viruses can have. To give an example in humans, when HIV-1-infected patients are also infected with hepatitis G virus, progression to AIDS is slowed significantly (Heringlake et al., 1998; Tillmann ...


22

This is because rabies is a viral infection of nervous tissue that propagates through peripheral nerves into the brain and causes brain tissue inflammation (encephalitis). As long as the virus is in the brain there is no way to get rid of it. The main trade-off here is that everything that would kill the virus will be as (or even more) aggressive against ...


19

This is probably a fly killed by the fungi Entomophthora muscae (or closely related) or maybe a Cordyceps fungus. These kinds of fungi mainly attacks insects, and you sometimes see attacks as white, swollen abdomens in flies. (Picture of common infection, from bugguide.net) These fungi are also known to change the behaviour of infected individuals, so ...


18

The reasons why HIV is "incurable" (a misnomer) are legion: HIV is a retrovirus, which means it inserts its own genome into the host cell's genome. You must therefore kill each and every infected cell to rid the body of the virus. HIV is a lentivirus, which means it has a long incubation period, so it can "lay low" before symptoms are readily detected. HIV ...


17

Yes, plants of all sizes can have cancerous growths. Agrobacterium tumifaciens, the causative agent of crown gall disease, produces what is called a tumor. See this link for detailed information on these growths. Alternatively, use a plant physiology textbook to look up the above terms. (Here, is where a textbook is better than a single abstract in PubMed.) ...


17

I think no one can really deny the existence of HIV or AIDS, just a search on google scholar will show >1,500,000 hits for each of those terms, and ask (hopefully any) doctor and they will say it does, though AIDS denialists do debate whether HIV causes AIDS. This paper explains the process of HIV causing AIDS. Further, AIDS denialists have not offered up ...


17

A mosquito's proboscis isn't like that of a butterfly, which could easily have nectar clinging to it when it is coiled up; instead, consider that the part of the mosquito's proboscis that enters a blood vessle is probably wiped clean when it is retracts outward through the epithelium. A a dirty needle or razor is many, many times larger than the sucking ...


16

I'm sure it varies wildly based on the animal and what they're eating. In general, if in the course of an animal's natural feeding process it picks up a little dirt, it has evolved to cope with that. Animal's behaviors and guts have evolved to fit their food source and lifestyle. For a behavioral example, seals will eat rough rocks to help breakdown bones ...


15

The question title and the question itself ask two slightly (but critically) different questions. Can cancers caused due to viruses be contagious? NO Are these oncoviruses infectious in nature? YES The tumors caused by the viruses are not contagious. You can't take the tumor and transfer it to a new host and see a new cancer. The viruses that cause the ...


13

Alright, having read the citation linked, and doing a little poking of my own, here's my approach at an answer: Some human herpes virus infections may compete with HIV infection. Essentially, some strains (not the ones you normally think of) infect CD4 cells - the same cells targeted by HIV. These strains down regulate transcription in CD4 cells, which in ...


12

Disclaimer: I'm an infectious disease modeler, and generally pretty skeptical of "We modeled X like an outbreak!" claims, because many are just an exercise in curve fitting. Given that, the answer is both "Yes" and "No". "No": Murder as an act really isn't transmissible, and if its not transmissible, it can't be modeled as an infectious disease. "Yes": It ...


12

The combination of these two reports from the CDC give information about the comparative prevalence of flu infection in the winter (September '12- May '13) and summer (May '13 - September '13). I'm going to assume that 2012-2013 was a fairly representative year as far as the level of detail of "do we get sick more in the winter" goes. Particularly striking ...


12

This is too long for a comment, so I put this in here: The main reasons are sociological. From the data I have read so far, this outbreak (actually these are two independent outbreaks, one in West-Africa and another one -not connected- in the Democratic Republic of Congo) is not exceptionally deadly in terms of Ebola. The death rate is about 60% which is ...


12

A cancer is not a pathogen Cancer is a group of cells that (because of several specific mutations) start to duplicate abnormally. This group of cancerous cells are the own cells of the sick patient. It is not another species infecting the individual carrying the disease. It is the individual itself who developed the disease. Cancer is not a pathogen (but ...


12

This is a great question. Just to make it clear people with DS do have a reduced risk of solid cancers and an increased risk of blood cancers, (B-ALL and AML). You are correct in picking out DSRC1 because of its angiogenic implications. The current hypothesis centers around people with DS being less capable of driving angiogenesis, and therefore having an ...


12

Short answer People with androgen insensitivity syndrome do not have a functional uterus and cannot bear a child. Background Androgen-insensitive genetic males may develop female genitalia and internal female reproductive organs. However, in both partial androgen insensitivity syndrome (PAIS) and complete androgen insensitivity syndrome (CAIS) the uterus is ...


12

I am not a medical doctor but in my view this is within the realms of possibility. The probability has been estimated by Princeton at 1 in 10 million. This is per bite, assuming - I presume - that the mosquito that bit you was just feeding on an HIV-infected person of sufficiently high viral load. It is not against the laws of Physics that blood cells can ...


12

No not white or grey generally, it's a mix of other colors, they often have low resolution of a particular color. Here's a page where you can mouse over a color wheel and see a version in color blind mode: http://www.archimedes-lab.org/colorblindnesstest.html The first type of cone is primarily sensitive to short wavelengths (blue), another to medium ...


12

Yes, Oncoviruses are infectious in nature. A good example is the Human Papilloma Virus, which does not immediately cause cancer, but can cause precancerous lesions in infected regions including cervix, vulva, vagina, penis, anus, mouth, or throat (see references 1 and 2). HPV is transmitted during sexual activities (hence the broad range of infected tissues ...


11

For some background, it is essential to know that Ebola is actually a group (genus) of ebolaviruses, each with different fatality rates. There are five known species of Ebola, and four are known to cause disease humans (WHO: Ebola virus disease; wikipedia). The known species of Ebola includes: Zaire ebolavirus (or just ebolavirus) Sudan ebolavirus ...


11

Thank you for the fascinating question! It was tough to research but very worthwhile. LDL is actually not such a bad molecule. It is formed from VLDL/IDL after VLDL/IDL distribute triglycerides, phospholipids, cholesterol and cholesterol esters to peripheral cells. With less to give, LDL subsequently tries to be helpful by providing any needy peripheral ...


10

In general antibiotics don't help with viruses. However, sometimes a bacterial infection may follow a cold virus, so there might be some scenarios in which antibiotics would be needed. However in many cases it could be due to people demanding antibiotics from their doctor. You can read more here (CDC site): http://www.cdc.gov/Features/getsmart/


10

it does not, really. unless we're talking about things like frostbite or severe hypothermia. it's a myth that it does. the virus is more stable in colder air, however. see more here: Study Shows Why the Flu Likes Winter Influenza Virus Transmission Is Dependent on Relative Humidity and Temperature Innate responses proved to be comparable between ...


10

I'm not sure if I should be posting this as an answer, but I think a very approachable and accurate account of the history of HIV can be found from Dinis de Sousa et al.. I agree with what has been posted above. On the theory that a picture is worth a thousands words, you might also introduce skeptics to the cryo-electron microscopy images of the virus (...


10

There is both a set "list" of agents, but more importantly, a set of properties that an organism needs to be in order to be truly worrisome. First, the list: The CDC classifies agents into one of three categories, Class A, B, or C. Class A: These are organisms that are hard to control, highly transmissible, and lethal: Anthrax (Bacillus anthracis) ...


9

Alzheimer's disease is a very complex field, and I am going to restrict my answer to two particular areas: the neuritic plaques and the neurofibrillary tangles. This area is also of interest to me, hence the protracted answer. The two pathological hallmarks of Alzheimer's disease, first described by Alois Alzheimer in about 1906, are the extracellular ...


9

I have never heard about this phenomenon from my patients or professors at the Medical School, but this is a possible mechanism that comes to my mind. One of the classification for antibiotics takes consideration the effect on bacteria. Two possible effects are either stopping the proliferation (and letting the immune system to kill those that are currently ...


9

There is the term “corset liver”. It describes changes (“grooves”) on the liver’s surface following external compression and subsequent local atrophy, e.g. from wearing a corset for a long time. (see Dancygier: Clinical Hepatology) A paper from the 1980s describes some abnormality in the histological findings of liver tissue of dogs after chronic abdominal ...


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